X-ray spectroscopy unveiling the working mechanisms and improving sustainable phosphate organo-mineral fertilizer technology.

Phosphate-based organo-mineral fertilizer technology has performed better than conventional fertilizers in several trials. We hypothesize that the organic phase in the pellet is: i) controlling P release; ii) preventing inner pellet P precipitation; ii) and bocking the P adsorption sites in the soil. We propose to employ the μ-XRF and μ-XANES techniques available at ID21 to investigate the P physical-chemical dynamics within and around the fertilizer pellet. The high sensititivity chemical maps recorded at a micrometer spatial resolution, combined with the P chemical speciation will allow us to test the above raised hypotheses, provide insights on the working mechanisms, and help to stablish a rational roadmap to improve this green and sustainable technology.